Vertically well-aligned ZnO nanowire ultraviolet ͑UV͒ photodetectors were fabricated by spin-on-glass technology on ZnO:Ga/glass templates. With 2 V applied bias, it was found that dark current density of the fabricated device was only 2.0ϫ 10 −7 A/cm 2 . It was also found that UV-to-visible rejection ratio and quantum efficiency of the fabricated ZnO nanowire photodetectors were more than 1000 and 12.6%, respectively.

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A novel approach to enhancing the emission efficiency of InGaN/GaN multiple quantum wells via coupling to surface plasmons (SPs) in a periodic two‐dimensional silver array is demonstrated. A higher internal quantum efficiency and a higher light extraction efficiency are simultaneously achieved by engraving an array of nanoholes into the p‐GaN cladding layer, followed by partial filling with silver. By top excitation and collection from the top of the Ag‐incorporated light emitting diodes (LEDs), a 2.8‐fold enhancement in peak photoluminescence intensity is demonstrated. The proposed nanoengraving technique offers a practical approach to overcoming the limitation of the exponentially decayed SP field without sacrificing the thickness of the p‐GaN layer and to controlling the effective coupling energy. The approach is feasible for high‐power lighting applications.

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We report the growth of vertically well-aligned ZnO nanowires on ZnO:Ga/glass templates and the fabrication of resistive ZnO nanowire-based oxygen gas sensor. It was found that the ZnO nanowires are grown preferred oriented in the (002) direction with a small x-ray diffraction full-width-half-maximum. From high resolution transmission electron microscopy, scanning electron microscopy and micro-Raman measurements, it was found that the ZnO nanowires prepared in this study are single crystalline with good crystal quality. It was also found that measured sample resistance increased logarithmically as the oxygen gas pressure in the chamber was increased. Such a relationship suggests that the device is potentially useful for resistive oxygen gas sensing at room temperature.